Steering tuning and lane changes
Curve entry, path following and lane-change initiation are separate issues. Identify the behavior you intend to change before adjusting a value.
Back up first
Record vehicle, device, model, commit and current settings. Do not copy another vehicle's number, such as SteerMax 409, as a recommendation. Software settings and vehicle/safety limits are separate.
Read steering parameters
| Item | Meaning |
|---|---|
SteerActuatorDelay | 30 means 0.30 s; 0 uses learned LiveDelay. Higher values anticipate steering earlier |
SteerRatio and learning | Depend on vehicle, learning and path; do not change together with delay |
LateralTorqueAccelFactor | Stored multiplier ×0.001; 2500 means 2.500 |
CustomSteerMax / Delta | Advanced torque limits/rates; larger is not necessarily better |
Center-of-mass ratio also affects curve entry. Keep other SAD/SR settings fixed when comparing. Restore previous values and collect logs if steering oscillates, warnings occur or the vehicle departs the lane.
Who does what in a lane change?
| Actor | Responsibility |
|---|---|
| Driver | Check mirrors, blind spots and approaching traffic; choose the gap; cancel/intervene |
| carrotpilot | Check delay, torque, lane and BSD initiation conditions |
| Driving model | Generate a lane-change path after a request |
| Vehicle controller | Follow the model path within vehicle limits |
There is no general setting directly specifying lane-change angle, completion time or lateral movement speed. LaneChangeDelay waits before initiation; it does not set crossing speed.
Initiation settings
| Key | Values |
|---|---|
LaneChangeNeedTorque | -1 disables automatic changes from driver turn signals; 0 no separate torque confirmation; 1 requires driver torque |
LaneChangeDelay | Stored value ×0.1 s; 10 means 1 s |
LaneChangeBsd | -1 ignores BSD; 0 blocks automatic start during detection but permits torque override; 1 blocks even with torque |
Check mirrors/blind spots before indicating. Without torque confirmation, a change may start as soon as conditions are met. No BSD detection does not prove that no vehicle is approaching.
ONNX lane / BSD experiments
Manage these under Carrot Web → Settings → Driving control → Vehicle steering → ONNX lane/BSD. ShareData controls lane-type recognition. OnnxBsdEnabled is a separate camera-BSD toggle, off by default. Lane recognition and vehicle-native BSD can remain separate when it is off.
The original guide also documents ATC right-indicator and manual lane-change indicator experiments for specific configurations such as IONIQ 5 PE with Jetson USB2CAN. The manual-indicator option does not add automatic lane-change steering requests. Consult the detailed source only after checking the configuration and validation scope.
Source reference
Reference checked 2026-10-30 · carrot-wip · 10bf0a56.
openpilot/selfdrive/carrot_settings.json · docs/user/ko/settings.md · docs/user/ko/lane-change.md
The development branch continues to change. Check your device’s branch, commit and current settings together.